Novatek-electro OM-310, Руководство пользователя

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ОМ-310
NOVATEK-ELECTRO
Figure 2.2 -
ОМ
-310 connection to PC schematic
2.4.4.3. Communication protocol
The exchange between PC and
ОМ
-310 is effected via data packages. Data packet format is given in Table 2.1.
Table 2.1
START silence interval – over 2msec at 9600 baud transfer rate, or over 4 msec at 19200 baud
transfer rate
ADR
ОМ
-310 communication address (8 bit)
CMD Command code 8 bit
DATA 0 Data contents:
N*8 data bit (n<=24)
….
DATA (n-1)
CRC CHK low
CRC checksum
16 bit
CRC CHK high
END
silence interval – over 2msec at 9600 baud transfer rate, or over 4 msec at 19200 baud
transfer rate
2.4.4.4 CMD (command code) and DATA (data symbols)
Data symbols format depends on command codes.
Command code –0x03, n-words read.
For example, read 2 continuous words swapped from 210
2H in ОМ
-310 initial address with 01H communication
address (Table 2.2)
Table 2.2
Command message Response message
ADR 0x01 ADR 0x01
CMD 0x03 CMD 0x03
Start data address 0x21
0x02 Data amount, bytes 0x04
Data amount in words 0x00
0x02 Data contents by address 0x17
0x70
CRC CHK low 0x6F Data contents by address 0x00
0x00
CRC CHK high 0xF7 CRC CHK low 0xFE
CRC CHK high 0x5C
Command code 0x06, record – one word
Using this command is not recommended as recording incorrest data may lead to
ОМ
-310 failure.
Data recording is possible only to the programmable parameters addresses (Table 1.5), except for parameters
listed in Table 2.3.